Cinditional if for array

Question

Saeid 2017-12-17

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https://ww2.mathworks.cn/matlabcentral/answers/373418-cinditional-if-for-array

评论： Saeid 2017-12-17

I want to activate some function on two matrices (e.g. multiply them) depending on the condition that two matrices A & B are not empty. I tried the statement:

if A~=[] & B~=[]
      C=A.*B
end

but I receive the error message:

Error using  ~= 
Matrix dimensions must agree.

How can I correct this?

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Answer 1

Birdman 2017-12-17

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Change the if statement to

if numel(A)==0 && numel(B)==0

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Saeid 2017-12-17

在 MATLAB Online 中打开

Thanks, but I guess since I did not ask my question completely it seems like that your answer can help only partially. The original reason I ask the question is that I read the contents of an exel file that contains both text and numerical data, e.g.

      Normal Stress 100 300 500
        Shear Stress 50 70 30
        Deformation 200 900 500
      Tempereature 20 45 13

I usually use _ strcmpi_ to find the desired text and then assign values that are in the next columns. However, sometimes the excel file does no contain that text but I do not know beforehand, hence the original question. In this case I want MATLAB to figure if there is such an array (e.g. Deformation) and only if it exists then execute a certain command. How can I do that?

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